1. Technical Field
The embodiments herein generally relate to tube bending process and particularly relates to rotary tube bending process. The embodiments herein more particularly relates to high strength mandrels used in rotary tube bending process.
2. Description of the Related Art
Flexible mandrels have been used to support the walls of metal tubing as it is bent. Such mandrels generally consist of a rigid mandrel body and a series of ball or ring members, each of which is locked on to a rigid inner ball link. These links are flexibly interconnected so that the string of balls may flex during the bending or forming process. The routine availability of mandrels for a wide variety of tube bending operations with ordinary tubing materials has naturally stimulated interest in extending the limits of these techniques for the production of difficult bends involving a tight radii, compound bends, and bends in large diameter or thin walled tubes of the more exotic high strength metals and alloys.
In the existing tube bending technique, a mandrel having a rigid body section and a series of spherical ball or ring members are used, which are free to float or slide longitudinally and rotate transversely on a chain of flexibly interconnected rigid link members. The ball members are of the “reverse” or internally nesting type to provide closeness of pitch and to distribute the mechanical stress of the bending operation along the series of balls instead of concentrating it on the balls and links immediately within the portion of the tube undergoing deformation.
In any event, the links interconnecting the ball segments should be adequately strong to resist tube to mandrel tool frictional forces developed during bending operation. The conventional mandrels suffer a number of drawbacks which prevent their routine application in high volume production situations. The problems encountered include high rate of wear and breakage of the mandrel links due to large and concentrated mechanical stresses imposed on the links during bending operation. Also the mandrels require continuous time consuming adjustment and replacement of the parts makes the mandrels costly to use and substantially limited the application.
The presently available mandrels can move in all directions and can rotate around all axes, while the tube bending is performed only in one plane and hence requires rotation around only one axis.
Hence there is a need for to provide a tube bending mandrel having rotation around only one axis. Also there is a need to produce a mandrel with reduced manufacturing cost and time. Further there is a need to provide a tube bending mandrel with increased strength of link and reduced damage to the links.
The abovementioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.